Both a review of the literature and the data from our initial NIMH project provide compelling evidence that parent-training is a plausible means of increasing the availability, intensiveness, and cost-effectiveness of the treatment of autistic children as compared to direct clinic treatment. This is true with respect to direct measures of the children's behavior, measures of parent/child interactions in both home and laboratory setting, and measures of parent psychological and marital adjustment. However, the data also suggest that lack of generalization may be one of the most important factors limiting the success of treatment with autistic children. Parent-training is superior to clinic treatment to a large extent because the parent (treatment provider) is present in many different settings and at many different times. However, our data on the behavior of the children with strangers indicate that even though parent-training is superior to clinic treatment, generalization still presents serious problems. Therefore, in order to have truly generalized treatment results, it appears important to understand and improve the general learning environment. We have pilot data which suggest several possibilities for both improving generalization as well as simultaneously affecting other widespread areas of the children's learning. Therefore, we are proposing to conduct a series of interrelated experiments, including analyses of: (I) the characteristics of the treatment procedures which may especially influence the extent of acquisition and generalization; and (II) specific learning characteristics of autistic children which may especially affect acquisition and generalization.